Nutrition Knowledge and Self-Efficacy among Classroom Teachers from a Large Urban School District in Los Angeles County

Purpose: School teachers play a critical role in providing nutrition information to students. Yet, in order for teachers to be a valuable source of nutrition information, they must be equipped with adequate knowledge to be able to convey accurate information to students. The purpose of this study was to assess nutrition-related knowledge and self-efficacy of teachers from a large urban school district in Los Angeles County. Methods: Using a convenience sample, 59 teachers from six elementary schools completed a one time only questionnaire assessing knowledge of food groups and self-efficacy to implement nutrition activities in the classroom. Differences in teachers’ responses to questions on knowledge and self-efficacy by demographics were also assessed. Results: The overall mean nutrition knowledge and self-efficacy scores were 50.4% and 71.4% respectively. Differences in nutrition knowledge and self-efficacy by demographic characteristics were observed. Conclusion: This study demonstrates that teachers in our sample did not have adequate levels of nutrition knowledge, and may not have possessed the necessary skills to effectively deliver nutrition education to their students. Current efforts to train and educate teachers on nutrition are perhaps falling short of the level needed to effect change in students’ dietary behaviors

Quantitative Ultrasonic Characterization of Metal Matrix Composite Fiber/Matrix Interfacial Failure

The transverse properties of unidirectional titanium matrix composites (TMCs) are dominated by the fiber/matrix interfacial properties, residual stresses and the matrix mechanical response. Nimmer et al. [1] have pioneered the research on the role of the interface when the composites are under transverse loading. In their work, a characteristic “knee” has been observed in the transverse tensile stress-strain curve of a Ti-6A1-4V/SCS-6 composite. This “knee” occurs well below the stress level at which the matrix yields extensively. The comparisons of experimental results with finite element modeling indicate that the “knee” is due to the failure of a weak interface under the transverse loading

Optimization of Sound Pulse Generation for Photoacoustic Sensing Applications

Photoacoustically generated sound pulses are currently used in various NDT, NDE and sensing applications, often because this method generates ultrasound without touching the sample. The generation mechanisms are relatively well known, including directional patterns, sound pressures and damage thresholds for the laser intensity. Our study addresses the optimal conditions for sound generation for sensing purposes in a liquid using a low power diode pumped Nd:YAG pulse laser.</p

“But the moment they find out that you are MSM…”: a qualitative investigation of HIV prevention experiences among men who have sex with men (MSM) in Ghana’s health care system

Abstract: The prevalence of HIV in Ghana is 1.3%, compared to 17% among men who have sex with men (MSM). There is limited empirical data on the current health care climate and its impact on HIV prevention services for Ghanaian MSM. The purposes of this study were to investigate (1) MSM’s experiences using HIV prevention resources, (2) what factors, including health care climate factors, influenced MSM’s use of prevention resources and (3) MSM self-identified strategies for improving HIV/sexually transmitted infection (STI) prevention among MSM in Ghanaian communities. Methods: We conducted 22 focus groups (n = 137) with peer social networks of MSM drawn from three geographic communities in Ghana (Accra, Kumasi, Manya Krobo). The data were examined using qualitative content analysis. Interviews with individual health care providers were also conducted to supplement the analysis of focus group findings to provide more nuanced illuminations of the experiences reported by MSM..

Responses to Diotic, Dichotic, and Alternating Phase Harmonic Stimuli in the Inferior Colliculus of Guinea Pigs

Humans perceive a harmonic series as a single auditory object with a pitch equivalent to the fundamental frequency (F0) of the series. When harmonics are presented to alternate ears, the repetition rate of the waveform at each ear doubles. If the harmonics are resolved, then the pitch perceived is still equivalent to F0, suggesting the stimulus is binaurally integrated before pitch is processed. However, unresolved harmonics give rise to the doubling of pitch which would be expected from monaural processing (Bernstein and Oxenham, J. Acoust. Soc. Am., 113:3323–3334, 2003). We used similar stimuli to record responses of multi-unit clusters in the central nucleus of the inferior colliculus (IC) of anesthetized guinea pigs (urethane supplemented by fentanyl/fluanisone) to determine the nature of the representation of harmonic stimuli and to what extent there was binaural integration. We examined both the temporal and rate-tuning of IC clusters and found no evidence for binaural integration. Stimuli comprised all harmonics below 10 kHz with fundamental frequencies (F0) from 50 to 400 Hz in half-octave steps. In diotic conditions, all the harmonics were presented to both ears. In dichotic conditions, odd harmonics were presented to one ear and even harmonics to the other. Neural characteristic frequencies (CF, n = 85) were from 0.2 to 14.7 kHz; 29 had CFs below 1 kHz. The majority of clusters responded predominantly to the contralateral ear, with the dominance of the contralateral ear increasing with CF. With diotic stimuli, over half of the clusters (58%) had peaked firing rate vs. F0 functions. The most common peak F0 was 141 Hz. Almost all (98%) clusters phase locked diotically to an F0 of 50 Hz, and approximately 40% of clusters still phase locked significantly (Rayleigh coefficient >13.8) at the highest F0 tested (400 Hz). These results are consistent with the previous reports of responses to amplitude-modulated stimuli. Clusters phase locked significantly at a frequency equal to F0 for contralateral and diotic stimuli but at 2F0 for dichotic stimuli. We interpret these data as responses following the envelope periodicity in monaural channels rather than as a binaurally integrated representation

Electrostatically driven synthetic microjet arrays as a propulsion method for micro flight

A propulsion system based on acoustic streaming generated by Helmholtz resonators is presented. High frequency (>60 kHz) electrostatically driven micromachined Helmholtz resonators constitute the basic unit of the system. Microjets produced at the exit of these resonators can be combined to form a distributed propulsion system. A high yield (>85%) fabrication process is introduced for fabrication of individual as well as arrays of resonators. The fabrication results for ten different designs are presented. About 1000 resonators of similar design cover the surface of a 4-in. wafer, effectively converting it to a distributed propulsion system. A number of characterization methods such as monitoring the harmonics of the drive current, laser interferometry, hot-wire anemometry, acoustic spectrum measurement and video particle imaging are used to determine the structural and fluidic behavior of different resonator designs. Collapse and recovery times of the diaphragm in the electrostatic actuator of the resonator are characterized and reduced to less than 10 μs by optimizing the perforation design. The occurrence of acoustic streaming in the micron-scale is verified via video particle imaging. The jet streams produced with pulse drive at low frequencies (~1 kHz) are spatially profiled and jet velocities exceeding 1 m/s are measured at the exit of the resonators. It has been verified that the resonance frequencies of the device at 50 and 175 kHz can be closely predicted by modeling.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47854/1/542_2005_Article_600.pd

Clinical spectrum of MTOR-related hypomelanosis of Ito with neurodevelopmental abnormalities

PURPOSE: Hypomelanosis of Ito (HI) is a skin marker of somatic mosaicism. Mosaic MTOR pathogenic variants have been reported in HI with brain overgrowth. We sought to delineate further the pigmentary skin phenotype and clinical spectrum of neurodevelopmental manifestations of MTOR-related HI. METHODS: From two cohorts totaling 71 patients with pigmentary mosaicism, we identified 14 patients with Blaschko-linear and one with flag-like pigmentation abnormalities, psychomotor impairment or seizures, and a postzygotic MTOR variant in skin. Patient records, including brain magnetic resonance image (MRI) were reviewed. Immunostaining (n = 3) for melanocyte markers and ultrastructural studies (n = 2) were performed on skin biopsies. RESULTS: MTOR variants were present in skin, but absent from blood in half of cases. In a patient (p.[Glu2419Lys] variant), phosphorylation of p70S6K was constitutively increased. In hypopigmented skin of two patients, we found a decrease in stage 4 melanosomes in melanocytes and keratinocytes. Most patients (80%) had macrocephaly or (hemi)megalencephaly on MRI. CONCLUSION: MTOR-related HI is a recognizable neurocutaneous phenotype of patterned dyspigmentation, epilepsy, intellectual deficiency, and brain overgrowth, and a distinct subtype of hypomelanosis related to somatic mosaicism. Hypopigmentation may be due to a defect in melanogenesis, through mTORC1 activation, similar to hypochromic patches in tuberous sclerosis complex

Listening geographies: Landscape, affect and geotechnologies

This paper argues for expanded listening in geography. Expanded listening addresses how bodies of all kinds, human and more-than-human, respond to sound. We show how listening can contribute to research on a wide range of topics, beyond enquiry where sound itself is the primary substantive interest. This is demonstrated through close discussion of what an amplified sonic sensibility can bring to three areas of contemporary geographical interest: geographies of landscape, of affect, and of geotechnologies